The field of the invention relates generally to a filtration method and system for removing particulate matter from a gas turbine air intake, and more particularly, to a filtration method and system that includes filter elements and electrostatic electrodes for removing particles from the gas turbine air intake.
Fabric and paper filtration are common techniques for separating out particulate matter in an air stream. Fabric and paper filtration are often accomplished in a device known as a baghouse. Known baghouses include a housing that has an inlet for receiving dirty, particulate-containing air and an outlet through which clean air leaves the baghouse. The interior of the housing is divided by a tube sheet into a dirty air or upstream plenum and a clean air or downstream plenum, with the dirty air plenum in fluid communication with the inlet and the clean air plenum in fluid communication with the outlet. The tube sheet typically includes a number of apertures and supports a number of filter elements with each filter element covering one of the apertures.
Known filter elements can include a support structure and a fabric or paper filter media. The support structure, which is also called a core, typically has a cylindrical shape and is hollow. The walls of the support structure may be similar to a screen or a cage, or may simply include a number of perforations, so that a fluid can pass through the support structure. The support structure has at least one end that is open and that is capable of being coupled to the tube sheet at an aperture. The support structure extends from the tube sheet into the dirty air plenum. There are several types of fabric and paper filter media. A “bag” filter media is flexible and/or pliable and is shaped like a bag. A cartridge filter media is relatively rigid and pleated. The filter media is mounted around the exterior or outer portion of the support structure.
During use, as particulate matter accumulates or cakes on the filters, the flow rate of the air is reduced and the pressure drop across the filters increases. To restore the desired flow rate, a reverse pressure pulse or other mechanical energy, for example, physically shaking or acoustic energy, is applied to the filters, or other mechanical energy. The reverse pressure pulse separates the particulate matter from the filter media, which then falls to the lower portion of the dirty air plenum.
Also, in a marine environment water and/or salt aerosols can cause excessive cake build-up on the filters, and can also deleteriously affect the operation of a gas turbine used for marine applications, for example, powering a ship. These water and/or salt aerosols can cause chemical corrosion of the component parts of the gas turbine.